Method of electric welding



(N0 Moqel.)

0. L. OOFFIN. METHOD OF ELECTRIC WELDING. No. 425,164. Patented Apr. 8, 1890.

I 1292 ,1 c Q I f a z 2' W UNITED STATES PATENT OFFICE.

CHARLES L. COFFIN, OF DETROIT, MICHIGAN.

METHOD OF ELECTRIC WELDING.

SPECIFICATION forming part of Letters Patent No. 425,164, dated April 8, 1890.

Application filed November 6, 1889. Serial No. 329,394. (No model.)

To all whom it may concern:

Be it known that I, CHARLES .L. COFFIN, of Detroit, in the county of Wayne and State of Michigan, have invented a new and useful Improvement in Electric W elding, of which the following is a specification.

My invention consists in a process of electric welding, hereinafter fully described and claimed.

Figure 1 is a perspective of an apparatus which may be used to practice my invention, and Fig. 2 is a vertical central section through the apparatus for re-enforcing a weld.

G represents a table, of Wood or other insulating material, provided with clamps M N, having set-screws P O, and connected by the conductors F Q with the opposite poles of a generator of electricity.

II II represent two articles to be welded together, laid on table G with their welding edges in contact and secured by the setscrews in the clamps M N.

A represents a conductor connected with F and with a binding-screw B on aconductor K, the end of which may terminate in a roller J, as shown, or may be a simple flat or rounded end. Resistance-coils A and F are located in the conductors for the purpose of directing the bulk of the circuit through either 'conductor at will, and more particularly for forming a voltaic arc between the points K and II II, as more particularly hereinafter described.

E is an insulating-handle on conductor K.

T T represent two insulated rollers on the ends of arms I I, which branch from the conductor K, and their purpose is to facilitate carryingthe lower end 011 conductor K along the joint, either in contact with or at a slight distance from II II. By placing the rollers T T out of line the lower end of K (the roller J, as shown) tilting the conductor will throw it in or out of contact with II II.

D represents a hollow conductor (carbon) carried on an insulating-handle E, connected with the conductor A, and C represents a wire or rod of metal like II II, passing down through conductor D. This is used when an irregularity, such as is shown at L, Fig. 2, is en countered in the welding edges of II II, the rod 0 melting and re-enforcing the joint at L.

My process is carried out as follows: II II being placed as shown in Fig. 1, the electric current is established through conductor F, clamp N, articles II II, clamp DI, and conductor Q, thus heating the edges of II II. The lower end of conductor K (roller J) is now brought in contact with the meeting edges of II II, thus shunting a part of the current through conductors A and K and increasing the local heating effect of the current of the edges of II II, and conductor K is traversed along said joint. An increased heating effect may be produced by bringing conductor K into contact with II II, thus establishing the circuit, then slightly raising conductor K, whereby a voltaic arc is formed between K and II II, and traversing the joint with the are. If an irregularity like L'is encountered, the conductor D is substituted for conductor K, and enough of wire O to fill the hole L is melted by the voltaic arc. hen the edges of II II are brought to a welding heat, the weld is formed by pressing II II together, and may be finished by rolling, hammering, or in any other known Way.

'What I claim as my invention, and desire to secure by Letters Patent, is

1. The herein-described process of welding metals electrically, consisting in placing the articles to be welded in contact, connecting them with opposite poles of a generator of electricity, passing a heating-current through them, simultaneously traversing the joint with an electric conductor, one end of which is connected with one pole of the generator and the other end in contact with the joint, and finally completing the weld by pressure.

2. The herein-described process of welding metal electrically, consisting in placing the articles to be welded in contact, connecting them with opposite poles of a generator of electricity, passing a heating-current through them, simultaneously traversing the joint with a voltaic arc sprung between the joint and a conductor connected with one pole of the. generator, and finally completin the weld by pressure.

3. The herein-described process of Welding metal electrically, consisting in placing the articles to be welded in contact, connecting them with opposite poles of a generator of electricity, passing a heating-current through them, simultaneously traversing the joint with a Voltaic arc sprung between the joint and a conductor connected with one pole of the generator, re-enforcing the joint by supplying like metal earried by the traversing 1o conductor and fused by the are,and finally completing the Weld by pressure.

CHARLES L. OOFFIN. Witnesses: c

CYRUS E. LoTHRoP, GERTRUDE ANDERSON. 

